Libration Crater on the Moon's Horizon | Peter Nerbun

Peter Nerbun
Location of photo
United States
Date/Time of photo
Oct 14 2013 0229UT
Celestron C11 SCT, ZWO ASI120MC camera, Losmandy G-11 mount
This photo shows one of the Moon's libration features appearing on the lunar horizon; this feature is Amundsen Crater. Because of the eccentricity of the Moon's orbit and the inclination of its poles the Moon oscillates in both longitude and latitude as seen from the Earth; this oscillatory motion is known as "Libration". Amundsen Crater appears near the horizon at the South Pole in this image which I captured on Oct 14 2013 but the crater sinks below the horizon 6 days later due to the aforementioned libration.
9505 Kingscroft Ter